PROJECT SUMMARY/ABSTRACT. Acquired autoimmune thrombotic thrombocytopenic purpura (TTP) is a rare disorder characterized by acute episodes of systemic microvascular thrombosis. TTP is more common in women, occurs during the child-bearing years, and rarely occurs in children <18 years of age. With early recognition and plasma exchange treatment, 78-90% of patients will survive their acute episode. Long-term adverse health outcomes in adults following recovery from TTP are under recognized. We have documented in the Oklahoma TTP Registry that survivors have an increased prevalence of major depression, decreased health-related quality of life, minor cognitive impairment, and a decreased life expectancy compared to the general population. However, current guidelines on the management of TTP focus on the long-term risk for relapse with no mention of patient-reported outcomes (PROs). We propose to utilize rigorous qualitative methods to determine from survivors the most important long-term outcomes that impact their daily routines during remission (Aim 1), which fills an existing gap by identifying specific PROMIS PROs that should be evaluated following recovery. Currently, there are no published studies on PROMIS instruments or the preferred mode of administration in TTP patients; therefore, we will determine the feasibility of administering PROMIS instruments online in a TTP population, including recruitment of TTP patients from the United States Thrombotic Microangiopathy Consortium (Aim 2). Understanding the TTP patient preference will assist in integrating these PROMIS instruments into routine clinical care. Finally, although it is becoming more common to integrate PRO assessments in routine clinical care, a barrier to successful integration is that clinicians are often unsure how to interpret PRO results in a clinically-meaningful way. Clinical severity cut-points such as `mild', `moderate' or `severe' may be more easily understood in a clinical setting than a comparison to a normative population. We propose to create clinical threshold levels for PROMIS scores (Aim 3) which fills an existing gap by reducing an implementation barrier for hematologists using PROMIS assessments to manage long-term outcomes. The rationale for the proposed study is that it is expected to yield important new insights into impairments during clinical remission of TTP and extend clinical interpretability of PROMIS measures to include a new disease area (TTP). Dr. Terrell is an Assistant Professor of Epidemiology at the University of Oklahoma Health Sciences Center. Her additional training proposed under the current career development plan will enhance her ability to become an independent NIH-funded clinical epidemiologist with training and experience in qualitative methodology and the theory and application of the measurement science of PROs.